1. Field of the Invention
The present invention relates to a night vision device (NVD). Particularly, the present invention relates to such a NVD which uses an image intensifier tube responding to light which may be either too dim or may be of a longer wavelength (i.e., infrared light) than can be seen using natural human vision. Thus, a scene illuminated by such light is substantially invisible to a human. Such a NVD using an image intensifier tube can provide a visible image replicating the scene. Still more particularly, the present invention relates to a method of operating such a NVD having an image intensifier tube.
2. Related Technology
NVD's are frequently used by military and law enforcement personnel for conducting operations in low light or at night. Devices which provide night vision and which use an image intensifier tube intensify the ambient light to produce an image which is visible to the human eye. Such NVD's may take a variety of forms. These various forms of NVD's may be categorized generally as follows:
a binocular having a separate objective lens, image intensifier tube, and eyepiece for each eye; PA1 a goggle having a single objective lens, single image intensifier tube, and a splitting prism supplying an image to each of two eyepieces; and PA1 a monocular having a single objective lens, single image intensifier tube, and single eyepiece.
Some such NVD's are also made as weapon sights generally having a configuration similar to an optical rifle sight, but including an image intensifier tube. These night vision weapon sights usually have a single image intensifier tube and single eyepiece.